The present invention is related to manufacturing techniques for optical fiber couplers and, more specifically, a torch useful in fusing optic fibers in an optical coupler.
In the manufacture of optical fiber couplers, optic fibers are typically fused together. In a general manufacturing process, two or more optical fibers having their outer coating removed are brought together and placed in contact with each other. The fibers may, or may not, be twisted together, depending upon the particular technique used to manufacture the coupler. Then a gas torch is brought close to the fibers and the flame from the torch placed in contact with the fibers. As the fibers are fused together by the flame's heat, the fibers are placed under tension by slowly and carefully pulling them apart at a predetermined rate.
Heretofore, torches with metal nozzles, such as illustrated in FIG. 1, have been used. These torches have certain disadvantages. The torches cannot be maintained in an ignited state because the temperature of the nozzles climb so high as to melt the nozzles. Therefore, the torches are lit for a fusing operation and then shut off until the next operation. This creates an additional step in the manufacturing operation, whether performed manually or by automated equipment. Another disadvantage is that nozzles tend to leave metal impurities in the fused fibers, thereby reducing optical performance.
The present invention solves or substantially mitigates any of these problems.